Most endoscopic procedures involve operation in natural cavities. Examples include laparoscopy, thoracoscopy, cystoscopy, arthroscopy, bronchoscopy, esophago-gastro-duodenoscopy, colonoscopy, colopscopy and hysteroscopy. Most other procedures, until recently have been performed through formal open procedures. Arthroscopy of the intervertebral disc has been practiced for nearly three decades now, but the disc space is a syndesmosis and lacks joint cavity. Attempts have been made to create an operating space in the retroperitoneal area to perform minimally invasive fusion of the lumbar spine. Arthroscopic Subacromial decompression is not an intra-cavitary procedure although one may start in the subacromial bursa.
With the successes of endoscopic procedures in most specialties of surgery, there is an increasing demand by patients for less invasive procedures, and efforts are being made by specialists in all surgical fields to find ways to satisfy this demand. When successful, the benefits are tremendous: the surgical time may be drastically reduced; surgical trauma is invariably less with endoscopic approaches; intra-operative and post-operative blood loss is usually minimal; hospital stay is short; rehabilitation is short and more complete than in cases of conventional procedures; the need for pain medication is less both in terms of the strength and duration of the medication; and return to productive activities is much earlier in most cases. In areas where there is no natural cavity, mini-open procedures are often performed to minimize surgical trauma and blood loss, but the trade-off may be a technically difficult procedure with less than satisfactory median or long term clinical outcome. While not always feasible, a new approach whereby an artificial working space is created to mimic a natural cavity, where one does not exist, is possible in many areas especially in the field of orthopedic and spine surgery, to facilitate endoscopic procedures such as anterior and posterior cervical spine procedures; posterolateral fusion of the lumbar spine, bone grafting of non-unions, repair of ruptured tendons and similar procedures.